It is desirable from a marketing standpoint to increase the storage or shelf life of various comestible products. This is accomplished by employing a sterilization process in conjunction with the forming, filling and sealing operations. Heretofore, sterilization of thermoplastic coated, liquid carrying paperboard containers has typically been accomplished on the forming, filling and sealing machine at a location between the station where the bottom formed container is stripped from an indexing mandrel and a station downstream thereof where the container is filled with a liquid, such as milk or juice. Such an arrangement is shown and described in Lisiecki U.S. Pat. No. 3,566,575, issued Mar. 2, 1971.
It is also known to use a sterilization apparatus and process wherein a channel is formed through the length of each mandrel of a typical indexing sprocket and mandrel assembly, with the channel communicating with openings and compartments formed in the hub of the indexing sprocket and mandrel assembly, such that as each mandrel reaches the 6:00 position, there is communication with a line leading from a generator which is capable of continuously producing a chlorine dioxide or hydrogen peroxide fog, thereby conveying such fog through the compartment and respective channels to the interior of each container as the latter is being mechanically stripped from the mandrel upon which it is slidably mounted. Such an arrangement is shown and described in commonly asigned Joosten and Davis patent application Ser. No. 368,940, filed Apr. 16, 1982 issued as U.S. Pat. No. 4,506,491 on Mar. 26, 1985.
As the effect of a sterilization process is dependent upon both sterilizing time and temperature, there is a need for a sterilization apparatus and method which maximizes both these variables on machines wherein the longitudinal distance between the mandrel and the filling station is limited.